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Saturday, March 28, 2009

Physics 3

Q-1 Length is a
(a) Scalar quantity
(b) Vector Quantity
(c) –IVE quantity
(d) None
Q-2 Torque is a
(a) Scalar quantity
(b) Vector quantity
(c) +IVE quantity
(d) None
Q-3 Angular velocity is a
(a) Polar vector
(b) Axial Vector
(c) Zero vector
(d) None
Q-4 Force is a
(a) Polar Vector
(b) Axial Vector
(c) a & b
(d) None
Q-5 When two vector, have equal magnitude & same direction then it is
(a) –VE vector
(b) Equal Vector
(c) a & b
(d) None
Q-6 What is magnitude of unit Vector?
(a) 1
(b) 2
(c) 3
(d) 5
Q-7 What will be the angle between two equal Vector?
(a) 00
(b) 10
(c) 11800
(d) 9000
Q-8 What will be the angle between two collinear vector?
(a) 21800
(b) 00
(c) 150
(d) None
Q-9 What thing unit vector tells us about vector?
(a) Direction
(b) Its speed
(c) Its Acc
(d) None
Q-10 What is unit of Unit vector?
(a) 0
(b) 1
(c) 3
(d) 8
Q-11 Zero vector is also called
(a) Collinear Vector
(b) Negative Vector
(c) Null Vector
(d) None
Q-12 Any vector whose end is fixed is called
(a) Localized Vector
(b) Delocalized Vector
(c) Free Vector
(d) None
Q-13 When we multiply a Vector quantity by a scalar quantity, ten the value obtain
(a) Vector Quantity
(b) Scalar Quantity
(c) Physical Quantity
(d) None
Q-14 When starting pt. of all the vector is same then it is
(a) Unit vector
(b) Co-initial vector
(c) Free vector
(d) None
Q-15 If velocity is uniform, then the value of acc is
(a) 0
(b) 1
(c) 2
(d) 3
Q-16 tan 450 =?
(a) 1
(b) 1/Ö2
(c) Ö3
(d) 5
Q-17 If we throw a ball upward then what will be its value at extreme height?
(a) 0
(b) 1
(c) 13
(d) 4
Q-18 When we apply brakes of a car, then it is a case of
(a) acceleration
(b) retardation
(c) Uniform velocity
(d) None
Q-19 If x = t4, then what will be its acc
At t = 2 sec
(a) 48m/sec2
(b) 45m/sec2
(c) 40m/sec2
(d) 50m/sec2
Q-20 If Q = 0 then what will be value of R
(a) 1
(b) P + Q
(c) P + 2Q
(d) 3P + 2Q
Q-21 What will be the angle between –IVE vector
(a) 00
(b) 900
(c) 1800
(d) None
Q-22 If a force F makes an angle Q with x – axis Then its vertical component will be
(a) F cos Q
(b) F SinQ
(c) F tan Q
(d) F cot Q
Q-23 When we add zero vector to any vector A, then its value is
(a) A
(b) 2A
(c) 3A
(d) 4A
Q-24 V = V0 + ……..
(a) at
(b) at3
(c) 2at
(d) None
Q-25 V2 – V02 = 2(…)
(a) at
(b) ax
(c) 2at2
(d) None

Answers:
1. a Scalar quantity
2. b Vector quantity
3. b Axial Vector
4. a Polar vector
5. b Equal
6. a 1
7. a 00
8. b 00
9. a Direction
10. a 0
11. c Null Vector
12. a Localized
13. a Vector Quantity
14. b Co-initial vector
15. a 0
16. a 1
17. a 0
18. b Retardation
19. a 48m/sec2
20. b P + Q
21. c 1800
22. b F sinQ
23. a A
24. a at
25. b ax

Solution:
19 x = + 4
V = dx/dt = 4 + 3
A = d2x/dt2 = 12t2
At t = 2 sec
a = 12(2)2 = 12(4) = 48m/sec2
20 If Q = 0
R2 = P2+ Q2 + 2PQ cos Ө
= P2 + Q2 + 2PQ cos Ө
= P2 + Q2 + 2PQ
R2 = (P + Q)2
R = P + Q

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